1. Field
The present disclosure relates to an electronic device, and more particularly, to a semiconductor memory device and an operating method thereof.
2. Discussion of Related Art
Semiconductor memory devices are generally classified into volatile memory devices and nonvolatile memory devices.
Nonvolatile memory devices have relatively low write and read rates, but are able maintain stored data without a constant source of power. Accordingly, nonvolatile memory devices are used to store data for situations there is not a constant power source. Nonvolatile memory devices include Read Only Memory (ROM), Mask ROM (MROM), Programmable ROM (PROM), Electrically Programmable ROM (EPROM), Electrically Erasable and Programmable ROM (EEPROM), flash memory, Phase-change RAM (PRAM), Magnetic RAM (MRAM), Resistive RAM (RRAM), Ferroelectric RAM (FRAM), and the like. Flash memory is generally divided between NOR and NAND types.
Flash memory has the advantages of RAM in that it can be freely programmed and erased, and the advantages of ROM in that it can store data without a constant source of power. Flash memory is widely used as a storage medium in portable electronic devices, such as digital cameras, Personal Digital Assistants (PDA), and MP3 players.